You know most of us would have trouble climbing 103 flights of stairs with two legs but can you imagine doing. With just one Zach potter did it Sunday using a bionic leg. -- to the top of Chicago's Willis tower one of the world's tallest buildings and he did it. To advance research in developing mind controlled prosthetic limbs for amputees actually climb the 2100 steps. Using his -- -- -- -- controlled prosthetic -- also arms these are becoming available commercially. Is especially advance it's years away from being so called. It is still it was remarkable. Yeah. A lot of people say they're losing a leg is like losing a loved one -- party your family. Content and you go through grieving process through all of that and it's. It's a long process to psychologically you overcome that and it. Put that behind you and established a new normal in your life and and move on --

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